Known within the art of water recreation are mechanisms for lifting boats out of the water for such purposes as making repairs or dry-docking. One such mechanism is shown in U.S. Pat. No. 5,184,914 (issued to S. Basta on Feb. 9, 1993), entitled LIFT FOR WATERCRAFT. The subject patent illustrates a frame that cradles the boat, lifting it from the water by means of a hydraulic ram. The frame contains four corner posts, or stanchions, for supporting the boat-and-frame combination. These corner posts have footings, or shoes, that rest on the bottom of the water. Sleeves attached to the frame slide on the corner posts. Once in position, these sleeves require that pins be placed through indexing holes in the corner posts, in order to secure the frame in the lifted position. This requires personnel to enter the water in order to place the pins into the holes. This is not only inconvenient, but is also inefficient, uncomfortable and potentially dangerous.
The frame corners are often unbalanced. What frequently occurs is that at least one post can be secured easily by a pin, while another post cannot. This, then, requires shims to be placed under the footings of the unsecured posts. The height of any given post may have to be adjusted, so that the pin will slip through one of the index holes in the sleeve adjacent a post hole. Such a procedure is fraught with danger and difficulty, owing to the facts that all of the above must be completed underwater and the boat-and-frame combination bears a tremendous weight upon the footing.
Another disadvantage of the aforementioned mechanism is the requirement of a hydraulic lift mechanism. To pump the hydraulic fluid therefor requires electrical power, which is certainly not always available at remote locations. A further disadvantage of such a device is the relative cost of having to supply a complex powered mechanism in order to lift a boat from the water.
The present invention seeks to provide a replacement corner post for devices such as the aforesaid boat-lift, so that difficult adjustments are eliminated.
Furthermore, one of the objectives of the present invention is to provide a corner post mechanism that can be adjusted above the water level, by means of an internal, mechanical worm drive. The worm drive of the inventive corner post can be manually cranked, or, if electricity is available, a small electrical motor can be used. The adjustments are made to each corner independently, one at a time, as needed. This eliminates the necessity for personnel to enter the water in order to adjust the post height.